Java tutorial
/* * Copyright 2016-present Open Networking Laboratory * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.onosproject.store.primitives.impl; import static com.google.common.base.Preconditions.checkNotNull; import java.util.Collection; import java.util.List; import java.util.Map; import java.util.Map.Entry; import java.util.Set; import java.util.TreeMap; import java.util.concurrent.CompletableFuture; import java.util.concurrent.Executor; import java.util.function.BiFunction; import java.util.function.Consumer; import java.util.function.Predicate; import java.util.stream.Collectors; import org.onlab.util.Match; import org.onlab.util.Tools; import org.onosproject.cluster.PartitionId; import org.onosproject.store.primitives.MapUpdate; import org.onosproject.store.primitives.TransactionId; import org.onosproject.store.service.AsyncConsistentMap; import org.onosproject.store.service.MapEventListener; import org.onosproject.store.service.MapTransaction; import org.onosproject.store.service.Versioned; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Lists; import com.google.common.collect.Maps; /** * {@link AsyncConsistentMap} that has its entries partitioned horizontally across * several {@link AsyncConsistentMap maps}. * * @param <K> key type * @param <V> value type */ public class PartitionedAsyncConsistentMap<K, V> implements AsyncConsistentMap<K, V> { private final String name; private final TreeMap<PartitionId, AsyncConsistentMap<K, V>> partitions = Maps.newTreeMap(); private final Hasher<K> keyHasher; public PartitionedAsyncConsistentMap(String name, Map<PartitionId, AsyncConsistentMap<K, V>> partitions, Hasher<K> keyHasher) { this.name = name; this.partitions.putAll(checkNotNull(partitions)); this.keyHasher = checkNotNull(keyHasher); } @Override public String name() { return name; } @Override public CompletableFuture<Integer> size() { return Tools.allOf(getMaps().stream().map(m -> m.size()).collect(Collectors.toList()), Math::addExact, 0); } @Override public CompletableFuture<Boolean> isEmpty() { return size().thenApply(size -> size == 0); } @Override public CompletableFuture<Boolean> containsKey(K key) { return getMap(key).containsKey(key); } @Override public CompletableFuture<Boolean> containsValue(V value) { return Tools.firstOf(getMaps().stream().map(m -> m.containsValue(value)).collect(Collectors.toList()), Match.ifValue(true), false); } @Override public CompletableFuture<Versioned<V>> get(K key) { return getMap(key).get(key); } @Override public CompletableFuture<Versioned<V>> computeIf(K key, Predicate<? super V> condition, BiFunction<? super K, ? super V, ? extends V> remappingFunction) { return getMap(key).computeIf(key, condition, remappingFunction); } @Override public CompletableFuture<Versioned<V>> put(K key, V value) { return getMap(key).put(key, value); } @Override public CompletableFuture<Versioned<V>> putAndGet(K key, V value) { return getMap(key).putAndGet(key, value); } @Override public CompletableFuture<Versioned<V>> remove(K key) { return getMap(key).remove(key); } @Override public CompletableFuture<Void> clear() { return CompletableFuture .allOf(getMaps().stream().map(map -> map.clear()).toArray(CompletableFuture[]::new)); } @Override public CompletableFuture<Set<K>> keySet() { return Tools.allOf(getMaps().stream().map(m -> m.keySet()).collect(Collectors.toList()), (s1, s2) -> ImmutableSet.<K>builder().addAll(s1).addAll(s2).build(), ImmutableSet.of()); } @Override public CompletableFuture<Collection<Versioned<V>>> values() { return Tools.allOf(getMaps().stream().map(m -> m.values()).collect(Collectors.toList()), (c1, c2) -> ImmutableList.<Versioned<V>>builder().addAll(c1).addAll(c2).build(), ImmutableList.of()); } @Override public CompletableFuture<Set<Entry<K, Versioned<V>>>> entrySet() { return Tools.allOf(getMaps().stream().map(m -> m.entrySet()).collect(Collectors.toList()), (s1, s2) -> ImmutableSet.<Entry<K, Versioned<V>>>builder().addAll(s1).addAll(s2).build(), ImmutableSet.of()); } @Override public CompletableFuture<Versioned<V>> putIfAbsent(K key, V value) { return getMap(key).putIfAbsent(key, value); } @Override public CompletableFuture<Boolean> remove(K key, V value) { return getMap(key).remove(key, value); } @Override public CompletableFuture<Boolean> remove(K key, long version) { return getMap(key).remove(key, version); } @Override public CompletableFuture<Versioned<V>> replace(K key, V value) { return getMap(key).replace(key, value); } @Override public CompletableFuture<Boolean> replace(K key, V oldValue, V newValue) { return getMap(key).replace(key, oldValue, newValue); } @Override public CompletableFuture<Boolean> replace(K key, long oldVersion, V newValue) { return getMap(key).replace(key, oldVersion, newValue); } @Override public CompletableFuture<Void> addListener(MapEventListener<K, V> listener, Executor executor) { return CompletableFuture.allOf(getMaps().stream().map(map -> map.addListener(listener, executor)) .toArray(CompletableFuture[]::new)); } @Override public CompletableFuture<Void> removeListener(MapEventListener<K, V> listener) { return CompletableFuture.allOf( getMaps().stream().map(map -> map.removeListener(listener)).toArray(CompletableFuture[]::new)); } @Override public CompletableFuture<Boolean> prepare(MapTransaction<K, V> transaction) { Map<AsyncConsistentMap<K, V>, List<MapUpdate<K, V>>> updatesGroupedByMap = Maps.newIdentityHashMap(); transaction.updates().forEach(update -> { AsyncConsistentMap<K, V> map = getMap(update.key()); updatesGroupedByMap.computeIfAbsent(map, k -> Lists.newLinkedList()).add(update); }); Map<AsyncConsistentMap<K, V>, MapTransaction<K, V>> transactionsByMap = Maps.transformValues( updatesGroupedByMap, list -> new MapTransaction<>(transaction.transactionId(), list)); return Tools .allOf(transactionsByMap.entrySet().stream().map(e -> e.getKey().prepare(e.getValue())) .collect(Collectors.toList())) .thenApply(list -> list.stream().reduce(Boolean::logicalAnd).orElse(true)); } @Override public CompletableFuture<Void> commit(TransactionId transactionId) { return CompletableFuture .allOf(getMaps().stream().map(e -> e.commit(transactionId)).toArray(CompletableFuture[]::new)); } @Override public CompletableFuture<Void> rollback(TransactionId transactionId) { return CompletableFuture .allOf(getMaps().stream().map(e -> e.rollback(transactionId)).toArray(CompletableFuture[]::new)); } @Override public CompletableFuture<Boolean> prepareAndCommit(MapTransaction<K, V> transaction) { Map<AsyncConsistentMap<K, V>, List<MapUpdate<K, V>>> updatesGroupedByMap = Maps.newIdentityHashMap(); transaction.updates().forEach(update -> { AsyncConsistentMap<K, V> map = getMap(update.key()); updatesGroupedByMap.computeIfAbsent(map, k -> Lists.newLinkedList()).add(update); }); Map<AsyncConsistentMap<K, V>, MapTransaction<K, V>> transactionsByMap = Maps.transformValues( updatesGroupedByMap, list -> new MapTransaction<>(transaction.transactionId(), list)); return Tools .allOf(transactionsByMap.entrySet().stream().map(e -> e.getKey().prepareAndCommit(e.getValue())) .collect(Collectors.toList())) .thenApply(list -> list.stream().reduce(Boolean::logicalAnd).orElse(true)); } @Override public void addStatusChangeListener(Consumer<Status> listener) { partitions.values().forEach(map -> map.addStatusChangeListener(listener)); } @Override public void removeStatusChangeListener(Consumer<Status> listener) { partitions.values().forEach(map -> map.removeStatusChangeListener(listener)); } @Override public Collection<Consumer<Status>> statusChangeListeners() { throw new UnsupportedOperationException(); } /** * Returns the map (partition) to which the specified key maps. * @param key key * @return AsyncConsistentMap to which key maps */ private AsyncConsistentMap<K, V> getMap(K key) { return partitions.get(keyHasher.hash(key)); } /** * Returns all the constituent maps. * @return collection of maps. */ private Collection<AsyncConsistentMap<K, V>> getMaps() { return partitions.values(); } }